Straight-Wire Appliances are all founded in the original principles of Dr. Andrews. That means that any A+ Straight-Wire Appliance is built upon three key Andrews principles: compound bracket contours, torque-in-base and level slot lineup. These design principles are interrelated and fundamental to the requirements of any Straight-Wire Appliance. And since all Straight-Wire Appliances share these principles, they are fully interchangeable.
Compound Contour Design
Mirrors both the mesiodistal and the occlusogingival anatomy of the middle third of every tooth’s clinical crown. This allows every Straight-Wire Appliance to fit snugly on the tooth for maximum efficiency. Compound contours greatly enhance accurate bracket placement on the center of the crown.
Level Slot Lineup
The end result of compound contours, torque-in-base and accurate bracket placement. The Straight-Wire Appliance is the only appliance that assures you that the slot of the bracket will always be parallel to the occlusal plane of the arch.
The key to uniformity of Straight-Wire bracket placement, ensuring high levels of predictability and accuracy in result. With every Straight-Wire Appliance, the center of the slot and the center of the base are always on the same plane for consistent and easy bracket placement.
Fully Programmed SWA
Genuine Straight-Wire Appliance brackets are fully programmed so that each tooth’s bracket slot lines up horizontally with all others to eliminate the need for time-consuming wire bends.
Partially Programmed Appliance
Even when attempts are made to align the slots of partially programmed brackets horizontally, the bracket heights vary from anterior to posterior, resulting in inconsistent and unpredictable torque and in/out compensation.